Mono-azo dyes and inks for ink-jet printing

ABSTRACT

A mono-azo compound of Formula (1) and salts thereof:                    
     wherein A, G, L 1 , L 2 , and R 1 , are defined in the specification, have especially good light fastness and other advantageous properties. These dyes may be used in inks, especially inks for ink jet printing inks and in ink jet printing processes to print substrates and to in ink jet printer cartridges.

This invention relates to dyes, to inks and to their use in ink jetprinting (“IJP”). IJP is a non-impact printing technique in whichdroplets of ink are ejected through a fine nozzle onto a substratewithout bringing the nozzle into contact with the substrate.

There are many demanding performance requirements for dyes and inks usedin IJP. For example they desirably provide sharp, non-feathered imageshaving good water-fastness, light-fastness and optical density. The inksare often required to dry quickly when applied to a substrate to preventsmudging, but they should not form a crust over the tip of an ink jetnozzle because this will stop the printer from working. The inks shouldalso be stable to storage over time without decomposing or forming aprecipitate which could block the fine nozzle.

According to the present invention there is provided a mono-azo compoundof Formula (1) and salts thereof:

wherein:

A is N, C—Cl, C—CN or C—NO₂;

R¹ is H or optionally substituted alkyl;

G is sulpho, carboxy, optionally substituted alkyl, optionallysubstituted alkoxy, —CF₃ or —PO₃H₂;

L¹ and L² are each independently —SR², —OR³ or —NR⁴R⁵;

R², R³, R⁴and R⁵ are each independently H, or alkyl or aryl each ofwhich is optionally substituted by a group other than sulphato or vinylsulphone; or

R⁴ and R⁵ together with the nitrogen to which they are attached form anoptionally substituted five or six membered ring;

provided that:

(a) L¹ and L² are free from carboxy, sulpho and —PO₃H₂ groups;

(b) L¹ and L² are not both —NH₂; and

(c) L¹ and L² are not both hydroxyethylamino.

The term mono-azo refers to a compound with one azo group (—N═N—).

Preferably A is N.

R¹ is preferably H or optionally substituted C₁₋₄-alkyl, more preferablyH or C₁₋₄-alkyl optionally substituted by hydroxy, carboxy, sulpho orcyano. Examples include methyl, ethyl, n-propyl, iso-propyl,hydroxyethyl, cyanoethyl, sulphopropyl and carboxyethyl. It isespecially preferred that R¹ is H.

G is preferably attached ortho to the azo group. Preferably G is —SO₃H,—COOH, —CF₃, alkyl (preferably optionally substituted C₁₋₄-alkyl),alkoxy (preferably optionally substituted C₁₋₄-alkoxy) or —PO₃H₂, morepreferably —SO₃H, —COOH or —CF₃ and especially —SO₃H. Preferred optionalsubstituents on G are selected from —OH, —COOH and —NH₂.

When R², R³, R⁴ or R⁵ is optionally substituted alkyl it is preferablyoptionally substituted C₁₋₃₀-alkyl. The alkyl group my be straight-chainor branched-chain. When it is a branched-chain alkyl, it is preferablyan α-branched alkyl group, for example —CH(CH₃)CH₂CH₂CH₃ or—CH(CH₃)CH₂CH(CH₃)₂. In one preferred embodiment the alkyl group isoptionally substituted C₁₋₁₀-alkyl, more preferably optionallysubstituted C₁₋₆-alkyl and especially optionally substituted C₁₋₄-alkyl.In another preferred embodiment the alkyl group is optionallysubstituted C₅₋₂₀-alkyl, more preferably C₉₋₂₀-alkyl.

Preferred optional substituents on the alkyl groups represented by anyof R², R³, R⁴ or R⁵ include hydroxy, cyano, halo (especially F or Cl),nitro, C₁₋₆-alkoxy, C₁₋₆hydroxyalkoxy, a 5 or 6 membered heterocyclicgroup, a group represented by T, wherein T is an optionally substitutedamino group and phenyl optionally substituted by one or more ofC₁₋₁₀-alkyl, hydroxy, cyano, halo, nitro, C₁₋₆-alkoxy,C₁₋₄-hydroxyalkoxy or a group T. Especially preferred substituents onthe alkyl group(s) are selected from hydroxy, a 5 or 6 memberedheterocyclic group and a group represented by T.

Preferred 5 or 6 membered heterocyclic groups are optionally substitutedfuranyl and tetrahydrofuranyl, more preferably furanyl ortetrahydrofuranyl and especially furan-2-yl and tetrahydrofuran-2-yl.

Preferably T is a group of the formula —NR⁶R⁷ wherein R⁶ and R⁷ are eachindependently H, optionally substituted alkyl, —CO(alkyl), —CO(phenyl),or R⁶ and R⁷ together with the nitrogen to which they are attached forman optionally substituted morpholinyl, piperazinyl or piperidinyl ring.

When R⁶ or R⁷ is optionally substituted alkyl it is preferablyoptionally substituted C₁₋₂₀-alkyl, more preferably optionallysubstituted C₁₋₆-alkyl, and especially C₁₋₄-alkyl, for example methyl,ethyl, n-propyl and iso-propyl. Preferred optional substituents on R⁶and R⁷ are selected from —OH and —NH₂.

When R⁶ or R⁷ is —CO(alkyl) it is preferably —CO(C₁₋₆-alkyl), morepreferably —CO(C₁₋₄alkyl). For example —COCH₂CH₃ and —COCH₂CH₂CH₃.

When R⁶ and R⁷ together with the nitrogen to which they are attachedform a substituted morpholinyl, piperidinyl or piperazinyl ring it ispreferably substituted by C₁₋₄-alkyl, C₁₋₄-hydroxyalkyl, —CO(C₁₋₄-alkyl)or a group of the formula —M—NR⁸R⁹ wherein M is an alkylene linkinggroup and R⁸ and R⁹ each independently is H or C₁₋₆-alkyl optionallysubstituted by hydroxy or C₁₋₆-alkoxy. M is preferably C₁₋₆-alkylene,more preferably C₂₋₆-alkylene and especially —(CH₂)_(g)—, where g isfrom 2 to 6.

Further preferred groups represented by T include —NH₂; —NH(C₁₋₃₀-alkyl)(preferably —NH(C₁₋₆-alkyl)), for example ethylamino, —NHCH(CH₃)CH₂CH₃and —NHC₁₆H₃₃; —N(C₁₋₆-alkyl)₂, for example di-ethylamino;—NHCO(C₁₋₄-alkyl), for example —NHCOCH₃ and —NHCOCH₂CH₃; —NH(Phenyl);morpholinyl optionally substituted by one or more C₁₋₄-alkyl groups, forexample morpholinyl, 2,6-dimethylmorpholinyl and 2-methylmorpholinyl;piperazinyl; and substituted piperazinyl groups of the Formula (2):

wherein:

Y is C₁₋₄-alkyl, hydroxy-C₁₋₄-alkyl, —CO(C₁₋₄-alkyl) or a group of theformula —M—NR⁸R⁹; and

M, R⁸ and R⁹ are as hereinbefore defined.

Preferred groups of the Formula (2) include for example:

A preferred alkyl group substituted by T which may be represented by anyof R², R³, R⁴ and R⁵ is of the formula —(C_(d)H_(2d))—T wherein d is 1to 6, more preferably 2 to 6 and T is as hereinbefore defined.

A further preferred optionally substituted alkyl group represented byany of R², R³, R⁴ and R⁵ is of the Formula (3):

—(C_(a)H_(2a)O)_(p)(C_(b)H_(2b)O)_(q)R¹⁰  Formula (3)

wherein:

R¹⁰ is H or alkyl optionally substituted by —NH₂ or;

a and b are different and from 1 to 6;

p is from 1 to 4; and

q is from 0 to 3.

Preferably R¹⁰ is H or C₁₋₄-alkyl, more preferably H.

Preferably a and b are each independently 2 to 6, more preferably 2 or3, p is 1 or 2 and q is 0.

Preferred groups of Formula (3) include—(C₂₋₆-alkylene)O(C₂₋₆-alkylene)OC₁₋₄alkyl, for example —C₂H₄OC₂H₄OCH₃,and —(C₂₋₆-alkylene)O(C₂₋₆-alkylene)OH, for example —C₂H₄OC₂H₄OH,—CH₂CH(CH₃)CH₂OC₂H₄OH and —C₃H₆OC₂H₄OH.

When R², R³, R⁴ or R⁵ is optionally substituted aryl it is preferablyoptionally substituted phenyl or optionally substituted naphthyl, morepreferably a group of the Formula (4) or (5):

wherein:

each R¹¹ independently is C₁₋₆-alkoxy, C₁₋₆-hydroxyalkoxy, hydroxy, halo(preferably F or Cl), nitro, amino, —COC₁₋₆-alkyl, —NHCOC₁₋₆-alkyl or—NHC₁₋₆-hydroxyalkyl;

each Q independently is optionally substituted C₁₋₃₀-alkyl or a group ofthe Formula —Z—Q¹;

each Z independently is a divalent linking group;

each Q¹ independently is optionally substituted C₁₋₃₀-alkyl;

n and m each independently is 0 to 5; and

(n+m)=to 5.

m is preferably 0, 1 or 2, more preferably 1 or 2.

n is preferably 0 or 1.

(n+m) is preferably 1 to 3 more preferably 1 or 2.

Each R¹¹ is preferably C₁₋₄-alkoxy, hydroxy-C₁₋₄-alkyl, hydroxy or Cl.

Each Z is preferably independently selected from —O—, —S—, —NR^(a)—,—SO₂NR^(a)— and —SO₂—, wherein R^(a) is H or C₁₋₃₀-alkyl optionallysubstituted by a group other than —COOH, —SO₃H or —PO₃H₂. PreferablyR^(a) is H or C₁₋₂₀-alkyl, more preferably H or C₁₋₆-alkyl andespecially H.

Q and Q¹ may be a straight chain or branched chain alkyl group. When anyof Q or Q¹ is a branched chain alkyl group it is preferably branched atthe a-carbon. In a preferred embodiment Q and Q¹ are each independentlyoptionally substituted C₁₋₄-alkyl. In a further preferred embodiment Qand Q¹ are each independently optionally substituted C₅₋₂₀-alkyl, morepreferably C₉₋₂₀alkyl.

When any of Q or Q¹ is substituted, the substituents are preferablyselected from hydroxy, cyano, halo (especially F or Cl), nitro,C₁₋₆-alkoxy, C₁₋₆-hydroxyalkoxy, a 5 or 6 membered heterocyclic group,or a group represented by T, wherein T is as hereinbefore defined. It ispreferred, however, that Q and Q¹ are unsubstituted.

Preferably R⁴ and R⁵ are not both optionally substituted aryl.

When R⁴ and R⁵ together with the nitrogen to which they are attachedform an optionally substituted 5 or 6 membered ring it is preferably anoptionally substituted piperazinyl, piperidinyl or morpholinyl ring. Thesubstituents are preferably selected from hydroxy, C₁₋₆-alkoxy,hydroxy-C₁₋₆-alkoxy, C₁₋₆-alkyl and C₁₋₆-alkyl substituted by hydroxy ora group represented by T as hereinbefore defined. More preferably thesubstituents are selected from C₁₋₆-alkyl or a group of the formula—C₁₋₆-alkylene-T. When R⁴ and R⁵ together with the nitrogen to whichthey are attached form a substituted piperazinyl ring it is preferablysubstituted on a nitrogen atom of the ring.

It is especially preferred that when R⁴ and R⁵ together with thenitrogen to which they are attached form a 5 or 6 membered ring it ismorpholinyl or piperazinyl optionally substituted by C₁₋₄-alkyl orC₁₋₄-hydroxyalkyl.

Examples of preferred optionally substituted morpholinyl and piperazinylrings which may be formed by R⁴ and R⁵ together with the nitrogen towhich they are attached include:

It is preferred that R², R³, R⁴and R⁵ each independently is H,C₁₋₃₀-alkyl optionally substituted by hydroxy, a 5 or 6 memberedheterocyclic group or a group represented by T, or R⁴ and R⁵ togetherwith the nitrogen to which they are attached form an optionallysubstituted morpholinyl, piperidinyl or piperazinyl ring.

When L¹ or L² is —NR⁴R⁵ it is preferably a group of the formula —NHR⁵,morpholinyl or piperazinyl optionally substituted by C₁₋₆-alkyl or agroup of the formula —(C₁₋₆-alkylene)-T, wherein T and R⁵ are ashereinbefore defined.

When L¹ and/or L² is a group of the formula —NHR⁵ it is preferably ofthe formula —NHR^(b), wherein R^(b) is—(C₁₋₆-alkylene)O(C₁₋₆-alkylene)OR¹⁰; a group of the Formula (4); orC₁₋₃₀-alkyl optionally substituted by furanyl, tetrahydrofuranyl, —OH,T, phenyl or phenyl substituted by one or more C₁₋₆-alkyl groups,wherein T, R¹⁰ and Formula (4) are as hereinbefore defined. PreferablyR^(b) is C₁₋₃₀-alkyl optionally substituted by furanyl,tetrahydrofuranyl, —OH or T wherein T is as hereinbefore defined. Morepreferably R^(b) is C₁₋₃₀-alkyl optionally substituted by two or more—OH groups. It is especially preferred that R^(b) is C₁₋₆-alkyloptionally substituted by two to five —OH groups. A further preferredgroup of the formula —NHR^(b) is of the formula —NH(C_(d)H_(2d))—Twherein d is 1 to 6.

In view of the foregoing preferences, a first preferred embodiment ofthe present invention are compounds of the Formula (6) and saltsthereof:

wherein:

X¹ and X² each independently is —O—, —S— or —NR¹²;

W¹ and W² each independently is H, a group T, —OC₁₋₆-alkylene —OR¹⁰,C₁₋₆-alkoxy, hydroxy, a 5 or 6 membered heterocyclic group or phenyloptionally substituted by one or more C₁₋₀-alkyl group(s);

R¹² is H or C₁₋₂₀-alkyl (preferably C₁₋₆-alkyl) optionally substitutedby hydroxy, C₁₋₄-alkoxy; or a group T;

p and q each independently is 1 to 20; or

X¹—(C_(p)H_(2p))W¹ and X²—(C_(q)H_(2q))W² each independently form apiperazine or morpholine ring optionally substituted by C₁₋₄-alkyl,hydroxy-C₁₋₄-alkyl, —CO(C₁₋₄-alkyl) or a group of the formula —M—NR⁸R⁹;and

M, R¹, R⁸, R⁹, R¹⁰ and T are as hereinbefore defined;

provided that:

(a) W¹, W² and R¹² are free from carboxy, sulpho and —PO₃H₂ groups; and

(b) the groups —X¹—(C_(p)H_(2p))—W¹ and —X²—(C_(q)H_(2q))—W² are notboth hydroxyethylamino.

In one preferred embodiment each p and q independently is from 1 to 6.In another preferred embodiment p and q independently is from 7 to 20,more preferably 9 to 20.

In a further preferred embodiment W¹ and W² each independently is H, agroup T, —OC₁₋₆-alkylene —OR¹⁰, C₁₋₆-alkoxy, hydroxy or a 5 or 6membered heterocyclic group, wherein T and R¹⁰ are as hereinbeforedefined.

The compounds of Formula (6) provide prints which exhibit a particularlyhigh light-fastness and good water-fastness when incorporated into inksfor ink jet printing. The compounds of Formula (6) are also highlysoluble which improves operability and reduces crusting when inkscontaining the compounds are used in an ink jet printer.

When W¹ or W² is a 5 or 6 membered heterocyclic group it is preferablypiperazinyl, morpholinyl, furanyl or tetrahydrofuranyl, more preferablyit is a morpholinyl, piperazinyl or tetrahydrofuran-2-yl group of theformula:

R¹² is preferably H or C₁₋₄-alkyl optionally substituted by hydroxy. Itis especially preferred that R¹² is H.

When —X¹—(C_(p)H_(2p))W¹ or —X²—(C_(q)H_(2q))W² form a piperazine ormorpholine ring preferred optional substituents are C₁₋₄-alkyl,hydroxy-C₁₋₄-alkyl, or a group of the formula —M—NR⁸R⁹, more preferablymethly ethyl and hydroxy-ethyl.

A second preferred embodiment of the present invention comprises acompound of Formula (6) and salts thereof wherein:

X¹ and X² are each independently —NR¹²— (preferably —NH—); and

W¹, W², R¹, R¹², p and q are as hereinbefore defined;

provided that:

(a) W¹, W² and R¹² are free from carboxy, sulpho and —PO₃H₂ groups; and

(b) The groups —X¹—(C_(p)H_(2p))—W¹ and —X²—(C_(q)H_(2q))—W² are notboth hydroxyethylamino.

A third preferred embodiment of the present invention comprises acompound of Formula (6) and salts thereof wherein:

X¹ and X² are each independently —NR¹²— (preferably —NH—);

W¹ and W² are each independently H, —NH₂, —NR¹³CO(C₁₋₄-alkyl)—OC₁₋₆-alkylene-OH, C₁₋₆-alkoxy morpholinyl or tetrahydrofuranyl;

R¹³ is H or C₁₋₄-alkyl; and

R¹² is as hereinbefore defined;

provided that W¹, W² and R¹² are free from carboxy, sulpho and —PO₃H₂groups.

A fourth preferred embodiment of the present invention comprises acompound of the Formula (7) or a salt thereof:

wherein:

R¹, X¹, X², W¹, Q, n, m and p are as hereinbefore defined;

provided that W¹, X¹, X² and each Q are free from carboxy, sulpho and—PO₃H₂ groups.

Especially preferred compounds of the Formula (7) are those wherein R¹is H or C₁₋₄-alkyl; X¹ and X² are each independently —S— or —NR¹²— (morepreferably —NH—), wherein R¹² is as hereinbefore defined; W¹ is H,tetrahydrofuranyl, —OH, phenyl or phenyl substituted by one or more C₁₋₄alkyl group(s); each Q independently is C₁₋₂₀-alkyl (more preferablyC₁₋₄-alkyl); m is 0, 1 or 2; n is 0 or 1 and p is 1 to 20 (morepreferably 5 to 20, and especially 9 to 20).

Further preferred compounds of Formula (7) are those wherein n=0 andeach Q independently is C₁₋₄-alkyl, more preferably those wherein n=0, mis 0, 1 or 2, each Q independently is C₁₋₄-alkyl and W¹ is H. We havefound that these compounds exhibit a high water-fastness.

A fifth preferred embodiment of the present invention comprisescompounds of the Formula (1) and salts thereof wherein G is —SO₃H and isattached ortho to the azo group; L¹ and L² independently are —NHR¹⁴wherein R¹⁴ is C₁₋₃₀-alkyl optionally substituted by two or more —OHgroups (more preferably C₁₋₆-alkyl optionally substituted by two to five—OH groups); and R¹ is H or C₁₋₄-alkyl.

The compounds of the invention may be in the free acid or salt form.Preferred salts are water-soluble, for example alkali metal salts,especially lithium, sodium and potassium salts, ammonium and substitutedammonium salts. Especially preferred alkali metal salts are those withsodium.

Especially preferred ammonium and substituted ammonium salts havecations of the formula ⁺NV₄ wherein each V independently is H oroptionally substituted alkyl, or two groups represented by V are H oroptionally substituted alkyl and the remaining two groups represented byV, together with the N atom to which they are attached, form a 5- or6-membered ring (preferably a morpholinyl, pyridinyl or piperidinylring).

Preferably each V independently is H or C₁₋₄-alkyl, more preferably H,CH₃ or CH₃CH₂, especially H. Thus the cation is preferably ammonium(i.e. ⁺NH₄).

Examples of cations include ⁺NH₄, morpholinium, piperidinium,pyridinium, (CH₃)₃N⁺H, (CH₃)₂N⁺H₂, H₂N⁺(CH₃)(CH₂CH₃),CH₃N⁺H₃,CH₃CH₂N⁺H₃, H₂N⁺(CH₂CH₃)₂, CH₃CH₂CH₂N⁺H₃, CH₃CH₂CH₂N⁺H₃, (CH₃)₂CHN⁺H₃,N⁺(CH₃)₄, N⁺(CH₂CH₃)₄, N-methyl pyridinium, N,N-dimethyl piperidiniumand N,N-dimethyl morpholinium.

The compounds may be converted into a salt using known techniques. Forexample, an alkali metal salt of a compound may be converted into a saltwith ammonia or an amine by dissolving an alkali metal salt of the dyein water, acidifying with a mineral acid and adjusting the pH of thesolution to pH 9 to 9.5 with ammonia or the amine and removing thealkali metal cations by dialysis.

The present invention covers all tautomeric forms of the dyes shown inthis specification, for example the hydrazo tautomers.

The present invention also covers mixtures comprising one or morecompounds of the Formula (1); and mixtures comprising one or morecompounds of the Formula (1) and one or more dye (preferably a magentadye), other than a compound of Formula (1). For example a mixturecomprising a compound of Formula (1) and one or more water-solublemagenta dyes selected from xanthene dyes, azo dyes (especially bis azodyes).

The compounds of the invention may be prepared using conventionaltechniques for the preparation of azo dyes. For example a suitablemethod comprises condensing a compound of the Formula (8) with acompound of the Formula L²H:

wherein A, R¹, G, L¹ and L² are as hereinbefore defined.

The condensation is preferably performed in a liquid medium, morepreferably an aqueous medium and especially water. Temperatures of 15°C. to 100° C. are preferred, more preferably from 60 to 70° C.Preferably a reaction time of 1 to 48, more preferably 3 to 24 hours isused.

The condensation is preferably performed in the presence of a base. Thebase may be any inorganic base for example, ammonia, an alkali metal oralkali earth metal hydroxide, carbonate or bicarbonate, or an organicbase. Preferred organic bases are tertiary amines for example,N-alkylated heterocycles, for example N—(C₁₋₄-alkyl)morpholine,N—(C₁₋₄-alkyl)piperidine, N,N′-di(C₁₋₄-alkyl)piperazine;tri(C₁₋₄-alkyl)amines, for example triethylamine, and optionallysubstituted pyridines, especially pyridine.

The amount of base used may be varied between wide limits but it ispreferred to use less than 40, more preferably less than 10 andespecially from 3 to 5 moles for each mole of the compound of Formula(8).

After the condensation the product may be isolated by precipitating theproduct as a salt from the reaction mixture for example by the additionof a suitable alkali metal salt, especially sodium chloride.Alternatively, the product may be isolated in its free acid form byacidifying the reaction mixture, preferably using a mineral acid,especially hydrochloric acid. Where the product precipitates as a solidit may be separated from the mixture by filtration.

If desired unwanted anions may be removed from the product of the aboveprocess by dialysis, osmosis, ultrafiltration or a combination thereof.

The product of the above process may be converted, if desired, to theNH₄ ⁺, quaternary ammonium or organic amine salt by the addition ofammonia, ammonium hydroxide, primary, secondary, tertiary or quaternaryamine. When the base used in the condensation process is an organicamine an excess may be used so that the compound of Formula (1) isformed as the organic amine salt.

The compound of the Formula (8) may be prepared using conventionaltechniques, for example by:

(1) diazotising the compound of the formula:

wherein G is as hereinbefore defined, to give the correspondingdiazonium salt;

(2) coupling the diazonium salt from stage (1) with2-amino-8-naphthol-6-sulphonic acid at a pH<7, preferably at a pH offrom 3 to 5;

(3) alkaline hydrolysis of the product of stage (2) to remove the acetylgroup;

(4) condensing the product from stage (1) with a compound of theformula:

wherein A is as hereinbefore defined; and

(5) condensing the product from stage (4) with approximately 1 molarequivalent of the compound of the formula L¹H.

The diazotisation in stage (1) is preferably performed in an aqueousmedium at a pH below 7 in the presence of a suitable diazotisationagent. Dilute mineral acid, e.g. HCl or H₂SO₄, is preferably used toachieve the desired acidic conditions. Conveniently the diazotisationagent is formed in-situ, for example by dissolving an alkali metalnitrite, preferably sodium nitrite, in a molar excess of mineral acid,preferably HCl. Normally at least one mole of diazotisation agent permole of the amine in stage (1), preferably from 1 to 1.25 moles will beused in the diazotisation.

The temperature of the diazotisation is not critical and mayconveniently be carried out at from −5° C. to 20° C., preferably from 0to 10° C. and especially from 0 to 5° C.

The hydrolysis in stage (3) is preferably performed at a pH in the range9 to 14. The temperature during hydrolysis is preferably from 40 to 90°C.

The compounds of Formula (1) are useful as dyes, especially for thecoloration of inks for ink jet printing.

According to a second aspect of the present invention there is providedan ink comprising:

(a) from 0.01 to 30 parts of a compound of the Formula (9); and

(b) from 70 to 99.99 parts of a medium comprising a mixture of water andan organic solvent, an organic solvent free from water, or a low meltingpoint solid;

wherein all parts are by weight and the number of parts of (a)+(b)=100:

wherein:

L³ is L¹ or a labile atom or group;

L⁴ is L² or a labile atom or group;

A, R¹, G, L¹ and L² are as hereinbefore defined;

provided that:

(a) L³ and L⁴ are free from carboxy, sulpho and —PO₃H₂ groups; and

(b) L³ and L⁴ are not both hydroxyethylamino.

When L³ or L⁴ is a labile atom or group, it is preferably an atom orgroup which is bound by a chemical bond to the compound of Formula (9)which is displaceable by a hydroxyl group of cellulose under mildlyalkaline aqueous conditions to form a covalent bond between the compoundof Formula (9) and cellulose.

Preferred labile atoms and groups represented by L³ and L⁴ includehalogen atoms, for example F and Cl; thiocyano groups; quaternaryammonium groups, for example trialkylammonium groups and optionallysubstituted pyridinium groups.

Preferably L³ is L¹ and L⁴ is L² as hereinbefore defined.

In the inks according to the second aspect of the present invention thecompound of Formula (9) is preferably of Formula (1), more preferably ofFormula (6) or (7), as hereinbefore defined.

The number of parts of component (a) is preferably from 0.1 to 20, morepreferably from 0.5 to 15, and especially from 1 to 5 parts. The numberof parts of component (b) is preferably from 99.9 to 80, more preferablyfrom 99.5 to 85, especially from 99 to 95 parts.

When the medium is a mixture of water and an organic solvent or anorganic solvent free from water, preferably component (a) is completelydissolved in component (b). Preferably component (a) has a solubility incomponent (b) at 20° C. of at least 10%. This allows the preparation ofconcentrates which may be used to prepare more dilute inks and reducesthe chance of the compound of Formula (9) precipitating if evaporationof the liquid medium occurs during storage.

When the medium comprises a mixture of water and an organic solvent, theweight ratio of water to organic solvent is preferably from 99:1 to1:99, more preferably from 99:1 to 50:50 and especially from 95:5 to80:20.

It is preferred that the organic solvent present in the mixture of waterand organic solvent is a water-miscible organic solvent or a mixture ofsuch solvents. Preferred water-miscible organic solvents includeC₁₋₆-alkanols, preferably methanol, ethanol, n-propanol, isopropanol,n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol andcyclohexanol; linear amides, preferably dimethylformamide ordimethylacetamide; ketones and ketone-alcohols, preferably acetone,methyl ether ketone, cyclohexanone and diacetone alcohol; water-miscibleethers, preferably tetrahydrofuran and dioxane; diols, preferably diolshaving from 2 to 12 carbon atoms, for example pentane-1,5-diol, ethyleneglycol, propylene glycol, butylene glycol, pentylene glycol, hexyleneglycol and thiodiglycol and oligo- and poly-alkyleneglycols, preferablydiethylene glycol, triethylene glycol, polyethylene glycol andpolypropylene glycol; triols, preferably glycerol and 1,2,6-hexanetriol;mono-C₁₋₄-alkyl ethers of diols, preferably mono-C₁₋₄-alkyl ethers ofdiols having 2 to 12 carbon atoms, especially 2-methoxyethanol,2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)-ethanol,2-[2-(2-methoxyethoxy)ethoxy]ethanol,2-[2-(2ethoxyethoxy)ethoxy]-ethanol and ethyleneglycol monoallylether;cyclic amides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone,N-ethyl-2-pyrrolidone, caprolactam and 1,3-dimethylimidazolidone; cyclicesters, preferably caprolactone; sulphoxides, preferably dimethylsulphoxide and sulpholane. Preferably the liquid medium comprises waterand 2 or more, especially from 2 to 8, water-soluble organic solvents.

Especially preferred water-soluble organic solvents are cyclic amides,especially 2-pyrrolidone, N-methyl-pyrrolidone and N-ethyl-pyrrolidone;diols, especially 1,5-pentane diol, ethyleneglycol, thiodiglycol,diethyleneglycol and triethyleneglycol; and mono-C₁₋₄-alkyl andC₁₋₄-alkyl ethers of diols, more preferably mono-C₁₋₄-alkyl ethers ofdiols having 2 to 12 carbon atoms, especially2-methoxy-2-ethoxy-2-ethoxyethanol.

A preferred medium comprises:

(a) from 75 to 95 parts water; and

(b) from 25 to 5 parts in total of one or more solvents selected fromdiethylene glycol, 2-pyrrolidone, thiodiglycol, N-methylpyrrolidone,cyclohexanol, caprolactone, caprolactam and pentane-1,5-diol;

wherein the parts are by weight and the sum of the parts (a) and(b)=100.

Examples of further suitable ink media comprising a mixture of water andone or more organic solvents are described in U.S. Pat. Nos. 4,963,189,4,703,113, 4,626,284 and EP 4,251,50A.

When the liquid medium comprises an organic solvent free from water,(i.e. less than 1% water by weight) the solvent preferably has a boilingpoint of from 30° to 200° C., more preferably of from 40° to 150° C.,especially from 50 to 125° C. The organic solvent may bewater-immiscible, water-miscible or a mixture of such solvents.Preferred water-miscible organic solvents are any of the hereinbeforedescribed water-miscible organic solvents and mixtures thereof.Preferred water-immiscible solvents include, for example, aliphatichydrocarbons; esters, preferably ethyl acetate; chlorinatedhydrocarbons, preferably CH₂Cl₂; and ethers, preferably diethyl ether;and mixtures thereof.

When the liquid medium comprises a water-immiscible organic solvent,preferably a polar solvent is included because this enhances solubilityof the compound of Formula (9) in the liquid medium. Examples of polarsolvents include C₁₋₄-alcohols. In view of the foregoing preferences itis especially preferred that where the liquid medium is an organicsolvent free from water it comprises a ketone (especially methyl ethylketone) &/or an alcohol (especially a C₁₋₄-alkanol, more especiallyethanol or propanol).

The organic solvent free from water may be a single organic solvent or amixture of two or more organic solvents. It is preferred that when themedium is an organic solvent free from water it is a mixture of 2 to 5different organic solvents. This allows a medium to be selected whichgives good control over the drying characteristics and storage stabilityof the ink.

Ink media comprising an organic solvent free from water are particularlyuseful where fast drying times are required and particularly whenprinting onto hydrophobic and non-absorbent substrates, for exampleplastics, metal and glass.

Preferred low melting solid media have a melting point in the range from60° C. to 125° C. Suitable low melting point solids include long chainfatty acids or alcohols, preferably those with C₁₈₋₂₄ chains, andsulphonamides. The compound of Formula (9) may be dissolved in the lowmelting point solid or may be finely dispersed in it.

The compounds of the Formula (9) exhibit a high solubility in aqueousmedia, accordingly it is preferred that the liquid medium is a mixtureof water and one or more water miscible organic solvent(s).

The composition may also contain additional components conventionallyused in ink jet printing inks, for example viscosity and surface tensionmodifiers, corrosion inhibitors, biocides, kogation reducing additivesand surfactants which may be ionic or non-ionic.

The compounds of the Formula (9) may be, and preferably are, purified toremove undesirable impurities before they are incorporated into inks forink jet printing. Conventional techniques may be employed for purifyingthe compounds, for example osmosis and/or dialysis.

When the inks according to the second aspect of the invention are usedas ink jet printing inks, the ink preferably has a concentration of lessthan 100 parts per million, more preferably less than 50 parts permillion, in total of undesirable ions, for example halide ions, siliconions, peroxide radicals and divalent and trivalent metals.

A third aspect of the present invention provides a process for printingan image on a substrate comprising applying thereto an ink containing acompound of Formula (9) as hereinbefore defined by means of an ink jetprinter.

The ink used in this process preferably comprises a composition asdefined in the second aspect of the present invention.

The ink jet printer preferably applies the ink to the substrate in theform of droplets which are ejected through a small orifice onto thesubstrate. Preferred ink jet printers are piezoelectric ink jet printersand thermal ink jet printers. In thermal ink jet printers, programmedpulses of heat are applied to the ink in a reservoir by means of aresistor adjacent to the orifice, thereby causing the ink to be ejectedin the form of small droplets directed towards the substrate duringrelative movement between the substrate and the orifice. Inpiezoelectric ink jet printers the oscillation of a small crystal causesejection of the ink from the orifice.

The substrate is preferably paper, plastic, a textile, metal or glass,more preferably paper, an overhead projector slide or a textilematerial, especially paper.

Preferred papers are plain or treated papers which may have an acid,alkaline or neutral character. Examples of commercially availabletreated papers include HP Premium Coated Paper (available from HewlettPackard), HP Photopaper (available from Hewlett Packard), Stylus Pro 720dpi Coated Paper, Epson Photo Quality Glossy Film (available from SeikoEpson Corp.), Epson Photo Quality Glossy Paper (available from SeikoEpson Corp.), Canon HR 101 High Resolution Paper (available from Canon),Canon GP 201 Glossy Paper (available from Canon), and Canon HG 101 HighGloss Film (available from Canon).

A fourth aspect of the present invention provides a paper, an overheadprojector slide or a textile material printed with an ink according tothe second aspect of the present invention, or by means of the processaccording to the third aspect of the present invention.

When the substrate is a textile material the ink according to theinvention is preferably applied thereto by:

i) applying the composition to the textile material using an ink jetprinter; and

ii) heating the printed textile material at a temperature of from 50° C.to 250° C.

Preferred textile materials are natural, synthetic and semi-syntheticmaterials. Examples of preferred natural textile materials include wool,silk, hair and cellulosic materials, particularly cotton, jute, hemp,flax and linen. Examples of preferred synthetic and semi-syntheticmaterials include polyamides, polyesters, polyacrylonitriles andpolyurethanes.

Preferably the textile material has been treated with an aqueouspretreatment composition comprising a thickening agent and optionally awater-soluble base and a hydrotropic agent and dried prior to step i)above.

The pre-treatment composition preferably comprises a solution of thebase and the hydrotropic agent in water containing the thickening agent.Particularly preferred pre-treatment compositions are described morefully in European Patent Application No.534660A1.

A fifth aspect of the present invention provides an ink jet printercartridge containing an ink, wherein the ink contains a compound of theFormula (9) as hereinbefore defined in relation to the second aspect ofthe present invention.

Preferably the ink in the ink jet printer cartridge is an ink accordingto the second aspect of the present invention.

The invention is further illustrated by the following Examples in whichall parts and percentages are by weight unless otherwise stated.

EXAMPLE 1

Dye

Dye (1) was prepared using the process described below:

Stage (1): Diazotisation and Coupling

To N-acetyl p-phenylenediamine sulphonic acid (0.5 moles) in water (400ml) was added concentrated hydrochloric acid (250 ml) and the solutionwas cooled to 0-5° C. 2N sodium nitrite (250 ml) was added dropwise over5 minutes with stirring. After 15 minutes, excess nitrous acid wasdestroyed by the addition of sulphamic acid (0.2 g). To the resultingsuspension was added a solution of 2-amino-8-naphthol-6-sulphonic acid(0.5 moles in 600 ml of water at pH6) and the pH was adjusted to 4 bythe addition of sodium acetate. The mixture was stirred at 0-5° C. for 4hours before being allowed to warm to room temperature.

Stage (ii) Hydrolysis

The acetyl group present on the product of stage (i) was removed byalkaline hydrolysis by adding concentrated sodium hydroxide (200 ml) tothe mixture resulting from stage 1 and heating at 70-80° C. for 1.5hours.

After cooling to room temperature, the pH was adjusted to 7 by theaddition of concentrated hydrochloric acid. Sodium chloride (20%weight/volume) was added and the precipitated solid was collected bysuction filtration, washed with 30% brine and dried at 70° C. Yield172.5 g (strength 52%).

Stage (iii) Condensation with Cyanuric Chloride

The product from stage (ii) (0.15 moles) was dissolved in water (500 ml)at pH7. Cyanuric chloride (0.17 moles) was dissolved in acetone (300 ml)and added dropwise over 10 minutes to the stirred solution at 0-5° C.The mixture was stirred for 40 minutes at this temperature.

Stage (iv) Further Condensation

2-aminoethyoxyethanol (0.5 mole) dissolved in water (400 ml) was addedto the mixture from stage (iii). The pH of the reaction mixture wasraised to 7 with 2N sodium hydroxide solution and this was maintainedwhilst the mixture was heated initially to 30-40° C. for 2 hours andfinally to 40-50° C. and at a pH of 8.5-9 for 16 hours.

The mixture was cooled to room temperature and evaporated to dryness.The solid was slurried in methylated spirits, collected by suctionfiltration and washed with further methylated spirits.

Stage (v) Purification

The product of stage (iv) was redissolved in distilled water anddialysed using Visking tubing to a permeate conductivity of below 100μS. The solution was evaporated to dryness. Yield 100 g.

Ink

Ink I was prepared by dissolving 2 parts of Dye (1) in 98 parts of amixture comprising 90 parts water and 10 parts 2-pyrrolidone.

Ink Jet Printing

Ink I was loaded into an Hewlett Packard 560C ink jet printer and wasprinted onto HP Premium Glossy Paper (available from Hewlett Packard).The resulting print was a bright magenta which had a good opticaldensity and excellent light fastness.

The optical density of the print was 2.29, as measured using an X-Ritedensitometer.

The print exhibited a ΔE value of 3 and an optical density loss of 11%after 64 hours irradiation in the Atlas Weatherometer.

The prints had a chroma of 75, as measured using an X-Rite densitometer.

EXAMPLES 2 to 11

Dyes of the general formula:

were prepared by condensing the product of stage (iii) in Example 1 withthe compound of the formula L¹H, at a reaction temperature of 30-40° C.for 2 hours, wherein L¹H is as shown in Table 1. The resultant productwas then isolated by adding 10% NaCl solution and reducing the pH to 4.5with 2N HCl.

The product of the above reaction (typically 0.13 moles) was thendissolved in dyes had the ΔE and reflected optical density (ROD) valuesshown in the final two column of Table 1.

TABLE 1 Example L¹H L²H ΔE ROD 2 HN(C₂H₄OH)₂ HN(C₂H₄OH)₂ 0.8 2.37 3HN(C₂H₄OH)₂ Morpholine 1.4 2.28 4 H₂NC₂H₄OH HN(C₂H₄OH)2 6.2 2.19 5Morpholine Morpholine 1.9 1.03 6 Morpholine 1-(2-aminoethyl)piperazine4.3 2.28 7 Morpholine 4-(2-aminoethyl)morpholine 2.6 2.07 84-(3-aminopropyl)morpholine 4-(3-aminopropyl)morpholine 3.1 2.56 94-(2-aminoethyl)morpholine 4-(2-aminoethyl)morpholine 2.4 2.24 10H₂NC₂H₄NHC(O)CH₃ H₂NC₂H₄NHC(O)CH₃ 3.1 2.08 11 TetrahydrofurfurylamineTetrahydrofurfurylamine 1.2 2.04

EXAMPLES 12 to 45

Further dyes of the general Formula (A) were prepared by condensing theproduct of stage (iii) in Example 1 with the compound of the formulaL¹H, followed by a further condensation with the compound L²H, whereinL¹H and L²H are shown in Table 2. The condensations were performed usinganalogous conditions to those described above for Examples 2 to 11.

The dyes provided bright magenta prints with a good optical density,water-fastness and high light-fastness when incorporated into inks whichwere applied to a paper substrate using an ink jet printer as describedabove in Example 1.

TABLE 2 Example L¹H L²H 12

13

14

15

16

17

18

19

20

— 21

— 22

— 23

24

25

26

27

28

29

30

— 31

— 32

33

34

35

36

37

38

— 39

— 40

— 41

42

43

44

45

46

A “—” in Table 2 indicates that a condensation was not performed (i.e.L² is —Cl)

EXAMPLES 47 to 55

Further dyes of the Formula (A) may be prepared by condensing theproduct of stage (iii) in Example 1 with the compound of the formulaL¹H, followed by a further condensation with the compound L²H, whereinL¹H and L²H are shown in Table 3.

TABLE 3 Exam- ple L¹H L²H 47

48 H₂NC₁₆H₃₃

49

50 HSC₁₀H₂₁

51 H₂N(CH₂)₆CH₃

52

53 H₂NC₁₆H₃₃

54

55

56 H₂NC₁₆H₃₃ H₂NC₁₆H₃₃

EXAMPLE 57

The inks described in Tables 4 to 7 may be prepared wherein the Dyedescribed in the first column is the Dye made in the above Example ofthe same number. Numbers quoted in the second column onwards refer tothe number of parts of the relevant ingredient and all parts are byweight. The ink may be applied to paper by thermal or piezo ink jetprinting.

The following abbreviations are used in Table 4 to 7:

PG=propylene glycol

DEG=diethylene glycol

NMP=N-methyl pyrrolidone

DMK=diethylketone

IPA=isopropanol

MEOH=methanol

2P=2-pyrrolidone

MIBK=methylisobutyl ketone

P12=propane-1,2-diol

BDL=butane-2,3-diol

CET=cetyl ammonium bromide

PHO=Na₂HPO₄ and

TBT=tertiary butanol

TDG=thiodiglycol

TABLE 4 Dye Na Dye Content Water PG DEG NMP DMK NaOH Stearate IPA MEOH2P MIBK 2 2.0 80 5 6 4 5 4 3.0 90 5 5 0.2 7 10.0 85 3 3 3 5 1 5 2.1 91 81 1 3.1 86 5 0.2 4 5 1 1.1 81 9 0.5 0.5 9 3 2.5 60 4 15 3 3 6 10 5 4 4 565 20 10 3 2.4 75 5 4 5 6 5 7 4.1 80 3 5 2 10 0.3 8 3.2 65 5 4 6 5 4 6 59 5.1 96 4 6 10.8 90 5 5 1 10.0 80 2 6 2 5 1 4 3 1.8 80 5 15 10 2.6 8411 5 4 3.3 80 2 10 2 6 11 12.0 90 7 0.3 3 6 5.4 69 2 20 2 1 3 3 7 6.0 914 5

TABLE 5 Dye Dye Content Water PG DEG NMP CET TBT TDG BDL PHO 2P PI2 23.0 80 15 0.2 5 3 9.0 90 5 1.2 5 5 1.5 85 5 5 0.15 5.0 0.2 7 2.5 90 6 40.12 6 3.1 82 4 8 0.3 6 11 0.9 85 10 5 0.2 2 8.0 90 5 5 0.3 8 4.0 70 104 1 4 11 4 2.2 75 4 10 3 2 6 5 10.0 91 6 3 7 9.0 76 9 7 3.0 0.95 5 9 5.078 5 11 6 11 5.4 86 7 7 3 2.1 70 5 5 5 0.1 0.2 0.1 5 0.1 5 4 2.0 90 10 22 88 10 5 5 78 5 12 5 3 8 70 2 8 15 5 7 10 80 8 12 6 10 80 10

TABLE 6 Dye Na Dye Content Water PG DEG NMP DMK NaOH Stearate IPA MEOH2P MIBK 20 2.0 80 5 6 4 5 40 3.0 90 5 5 0.2 17 10.0 85 3 3 3 5 1 15 2.191 8 1 13 3.1 86 5 0.2 4 5 14 1.1 81 9 0.5 0.5 9 15 2.5 60 4 15 3 3 6 105 4 16 5 65 20 10 1 2.4 75 5 4 5 6 5 2 4.1 80 3 5 2 10 0.3 6 3.2 65 5 46 5 4 6 5 9 5.1 96 4 10 10.8 90 5 5 11 10.0 80 2 6 2 5 1 4 12 1.8 80 515 13 2.6 84 11 5 14 3.3 80 2 10 2 6 15 12.0 90 7 0.3 3 16 5.4 69 2 20 21 3 3 17 6.0 91 4 5

TABLE 7 Dye Dye Content Water PG DEG NMP CET TBT TDG BDL PHO 2P PI2 183.0 80 15 0.2 5 23 9.0 90 5 1.2 5 19 1.5 85 5 5 0.15 5.0 0.2 20 2.5 90 64 0.12 22 3.1 82 4 8 0.3 6 21 0.9 85 10 5 0.2 28 8.0 90 5 5 0.3 29 4.070 10 4 1 4 11 30 2.2 75 4 10 3 2 6 31 10.0 91 6 3 32 9.0 76 9 7 3.00.95 5 33 5.0 78 5 11 6 34 5.4 86 7 7 35 2.1 70 5 5 5 0.1 0.2 0.1 5 0.15 36 2.0 90 10 37 2 88 10 38 5 78 5 12 5 39 8 70 2 8 15 5 40 10 80 8 1241 10 80 10

What is claimed is:
 1. A mono-azo compound of Formula (1) and saltsthereof:

wherein: A is N, C—Cl, C—CN or C—NO₂; R¹ is H or optionally substitutedalkyl; G is sulpho, carboxy, optionally substituted alkyl, optionallysubstituted alkoxy, —CF₃ or —PO₃H₂; L¹ and L² are each independently—SR², —OR³ or —NR⁴R⁵; R², R³, R⁴ and R⁵ are each independently H,optionally substituted alkyl or a group of the Formula (4) or Formula(5)

wherein: each R¹¹ independently is C₁₋₆-alkoxy, C₁₋₆-hydroxyalkoxy,hydroxy, halo, nitro, amino, —COC₁₋₆-alkyl, —NHCOC₁₋₆-alkyl or—NHC₁₋₆-hydroxyalkyl; each Q independently is optionally substitutedC₁₋₃₀-alkyl or a group of the Formula —Z—Q¹; each Z independently is adivalent linking group; each Q¹ independently is optionally substitutedC₁₋₃₀-alkyl; n is 0 to 5; m is 1 or 2; (n+m)=1 to 5; any optionalsubstituent on R², R³, R⁴ and R⁵ being other than sulphato or vinylsulphone; or R⁴ and R⁵ together with the nitrogen to which they areattached form an optionally substituted five or six membered ring;provided that: (a) L¹ and L² are free from carboxy, sulpho and —PO₃H₂groups; (b) L¹ and L² are not both —NH₂; and (c) L¹ and L² are not bothhydroxyethylamino.
 2. A compound according to claim 1 wherein G isattached ortho to the azo group.
 3. A compound according to either claim1 or claim 2 wherein G is sulpho.
 4. A compound according to any one ofthe preceding claims wherein A is N.
 5. A compound according to any oneof the preceding claims wherein: R², R³, R⁴ and R⁵ each independently isH or C₁₋₃₀-alkyl optionally substituted by one or more atoms or groupsselected from the group consisting of hydroxy, cyano, halo, nitro,C₁₋₆-alkoxy, C₁₋₆-hydroxyalkoxy, a 5 or 6 membered heterocyclic group, agroup represented by T and phenyl optionally substituted by one or moreof C₁₋₁₀-alkyl, hydroxy, cyano, halo, nitro, C₁₋₆-alkoxy,C₁₋₆-hydroxyalkoxy or a group T; or R⁴ and R⁵ together with the nitrogento which they are attached form an optionally substituted morpholinyl,piperazinyl or piperidinyl ring; and T is an optionally substitutedamino group.
 6. A compound according to claim 1 of the Formula (6) andsalts thereof:

wherein: X¹ and X² each independently is —O—, —S— or —NR¹²; W¹ and W²each independently is H, a group T, —OC₁₋₆-alkylene —OR¹⁰, C₁₋₆-alkoxy,hydroxy, a 5 or 6 membered heterocyclic group or phenyl optionallysubstituted by one or more C₁₋₁₀-alkyl group(s); R¹⁰ is H or alkyloptionally substituted by —NH₂; R¹² is H or C₁₋₂₀-alkyl optionallysubstituted by hydroxy, C₁₋₄-alkoxy; or a group T; T is an optionallysubstituted amino group; p and q each independently is 1 to 20; orX¹—(C_(p)H_(2p))W¹ and X²—(C_(q)H_(2q))W² each independently form apiperazine or morpholine ring optionally substituted by C₁₋₄-alkyl,hydroxy-C₁₋₄-alkyl, —CO(C₁₋₄-alkyl) or a group of the formula —M—NR⁸R⁹;R⁸ and R⁹ each independently is H or C₁₋₆-alkyl optionally substitutedby hydroxy or C₁₋₆-alkoxy; M is C₁₋₆-alkylene; and R¹ is optionallysubstituted alkyl; provided that: (a) W¹, W² and R¹² are free fromcarboxy, sulpho and —PO₃H₂ groups; and (b) the groups—X¹—(C_(p)H_(2p))—W¹ and —X²—(C_(q)H_(2q))—W² are not bothhydroxyethylamino.
 7. A compound according to claim 6 wherein: X¹ and X²are each independently —NR¹²—; and R¹² is as defined in claim
 6. 8. Acompound according to claim 6 wherein: X¹ and X² are each independently—NR¹²; W¹ and W² are each independently H, —NH₂, —NR¹³CO(C₁₋₄-alkyl),—OC₁₋₆-alkane-OH, C₁₋₆-alkoxy, morpholinyl or tetrahydrofuranyl; R¹³ isH or C₁₋₄-alkyl; and R¹² is as defined in claim
 6. 9. A compoundaccording to claim 1 of the Formula (7) or a salt thereof:

wherein: each Q independently is optionally substituted C₁₋₃₀-alkyl or agroup of the Formula —Z—Q¹; each Z independently is a divalent linkinggroup; each Q¹ independently is optionally substituted C₁₋₃₀-alkyl; eachR¹¹ independently is C₁₋₆-alkoxy, C₁₋₆-hydroxyalkoxy, hydroxy, halo,nitro, amino, —COC₁₋₆-alkyl, —NHCOC₁₋₆-alkyl or —NHC₁₋₆-hydroxyalkyl; mis 0 to 5; n is 0 to 5; (n+m)=0 to 5; p is 1 to 20; and R¹, isoptionally substituted alkyl, W¹ and W² each independently is H, a groupT, —OC₁₋₆-alkylene —OR¹⁰, C₁₋₆-alkoxy, hydroxy, a 5 or 6 memberedheterocyclic group or phenyl optionally substituted by one or moreC₁₋₁₀-alkyl group(s); X¹ and X² each independently is —O—, —S— or —NR¹²;provided that W¹, X¹, X² and each Q are free from carboxy, sulpho and—PO₃H₂ groups.
 10. A compound according to claim 9 wherein: R¹ is H orC₁₋₄-alkyl; X¹ and X² each independently is —S— or —NR¹²; W¹ is H,tetrahydrofuranyl, —OH, phenyl or phenyl substituted by one or moreC₁₋₄-alkyl group(s); each Q independently is C₁₋₂₀-alkyl; R¹² is H orC₁₋₂₀-alkyl optionally substituted by hydroxy; n is 0 or 1; and p is 1to
 20. 11. A compound according to claim 9 wherein: R¹ is H orC₁₋₄-alkyl; W¹ is H; n is 0; and each Q independently is C₁₋₄-alkyl. 12.A compound according to any one of claims 9 to claim 11 wherein p is 5to
 20. 13. A compound according to claim 1 wherein: G is —SO₃H and isattached ortho to the azo group; L¹ and L² each independently is —NHR¹⁴;R¹⁴ is C₁₋₃₀-alkyl optionally substituted by two or more —OH groups; andR¹ is H or C₁₋₄-alkyl.
 14. A compound according to any one of theprevious claims in the form of an alkali metal, ammonium or substitutedammonium salt.
 15. An ink comprising: (a) from 0.01 to 30 parts of acompound of the Formula (9); and (b) from 70 to 99.99 parts of a mediumcomprising a mixture of water and an organic solvent, an organic solventfree from water, or a low melting point solid; wherein all parts are byweight and the number of parts of (a)+(b)=100:

wherein: L³ is L¹ or a labile atom or group; L⁴ is L² or a labile atomor group; A, R¹, G, L¹ and L² are as defined in claim 1; provided that:(a) L³ and L⁴ are free from carboxy, sulpho and —PO₃H₂ groups; and (b)L³ and L⁴ are not both hydroxyethylamino.
 16. A process for printing animage on a substrate comprising applying thereto an ink containing acompound of the Formula (9)

wherein: L³ is L¹ or a labile atom or group; L⁴ is L² or a labile atomor group; A, is N, C—Cl, C—CN or C—NO₂; R¹ is H or optionallysubstituted alkyl; G is sulpho, carboxy, optionally substituted alkyl,optionally substituted alkoxy, —CF₃ or —PO₃H₂; L¹ and L² are eachindependently —SR², —OR³ or —NR⁴R⁵; provided that: (a) L³ and L⁴ arefree from carboxy, sulpho and —PO₃H₂ groups; and (b) L³ and L⁴ are notboth hydroxyethylamino, by means of an ink jet printer.
 17. A processaccording to claim 16 wherein the ink comprises (a) from 0.01 to 30parts of the compound of Formula (9); and (b) from 70 to 99.99 parts ofa medium comprising a mixture of water and an organic solvent, anorganic solvent free from water, or a low melting point solid; whereinall parts are by weight and the number of parts (a)+(b)=100.
 18. Apaper, an overhead projector slide or a textile material printed with anink according to claim
 15. 19. An ink jet printer cartridge containingan ink, wherein the ink contains a compound of the Formula (9)

wherein: L³ is L¹ or a labile atom or group; L⁴ is L² or a labile atomor group; A, is N, C—Cl, C—CN or C—NO₂; R¹ is H or optionallysubstituted alkyl; G is sulpho, carboxy, optionally substituted alkyl,optionally substituted alkoxy, —CF₃ or —PO₃H₂; L¹ and L² are eachindependently —SR², —OR³ or —NR⁴R⁵; provided that: (a) L³ and L⁴ arefree from carboxy, sulpho and —PO₃H₂ groups; and (b) L³ and L⁴ are notboth hydroxyethylamino.
 20. A paper, an overhead projector slide or atextile material printed by means of a process according to claim 16.